/// <summary>
/// Invoked when an unhandled DragDrop.DragEnter attached event reaches an element in its route that is derived from this class.
/// </summary>
/// <param name="dragEventArgs">The DragEventArgs that contains the event data.</param>
protected override void OnDrop(DragEventArgs dragEventArgs)
{
// Close (and dereference) the window used to display the object being dragged.
this.dragWindow.Close();
this.dragWindow = null;
// Attempt to find the element currently selected in the page. This item will be the parent of any object dropped onto the surface.
CategoryCollection parentItem = ExplorerHelper.FindExplorerItem(this.DataContext as CategoryCollection, this.Source) as CategoryCollection;
if (parentItem != null)
{
// We can import files dropped onto the surface. If the format specifies one or more files dragged from the Windows Explorer, then set call a
// handler to import each filed based on the file type (that is, the extension).
String[] paths = dragEventArgs.Data.GetData("FileDrop") as String[];
if (paths != null)
{
foreach (String path in paths)
{
ItemProperty externalObject;
if (CategoryPage.itemProperties.TryGetValue(Path.GetExtension(path).ToLower(), out externalObject))
{
CategoryPage.CreateItem(parentItem, path, externalObject);
}
}
}
}
}
/// <summary>
/// Initializes a new instance of a CategoryCollection class.
/// </summary>
/// <param name="parent">The parent of the category node.</param>
/// <param name="rootRow">The data model record that provides a context for this Model View.</param>
public CategoryCollection(CategoryCollection parent, DataSet.RootRow rootRow)
{
// Validate the parameters.
if (rootRow == null)
{
throw new ArgumentNullException("rootRow");
}
// Extract the values from the record.
this.Name = rootRow.Name;
this.Parent = parent;
this.rootIdField = rootRow.RootId;
this.typeIdField = rootRow.TypeId;
this.TypeDescription = rootRow.TypeRow.Name;
// This will disassemble the icon and give us the basic image sizes supported by the application framework.
Dictionary <ImageSize, ImageSource> images = ImageHelper.DecodeIcon(Convert.FromBase64String(rootRow.Image));
this.SmallImageSource = images[ImageSize.Small];
this.MediumImageSource = images[ImageSize.Medium];
this.LargeImageSource = images[ImageSize.Large];
this.ExtraLargeImageSource = images[ImageSize.ExtraLarge];
// These are the metadata properties of the item.
foreach (DataSet.PropertyStoreRow propertyStoreRow in rootRow.GetPropertyStoreRows())
{
this.PropertyStore.Add(propertyStoreRow.PropertyId, propertyStoreRow.Value);
}
// This will dig into the relations and recursively construct a hierarchy of items.
this.ExpandTree(rootRow);
}
/// <summary>
/// Creates a data model entry for the given path element.
/// </summary>
/// <param name="categoryCollection"></param>
/// <param name="path">The full file name of the object to be loaded.</param>
/// <param name="externalObject">The properties used to build the object.</param>
static void CreateItem(CategoryCollection categoryCollection, String path, ItemProperty externalObject)
{
// Create a new record for this object.
DataSet.RootRow rootRow = DataModel.DataSet.Root.NewRootRow();
rootRow.RootId = Guid.NewGuid();
rootRow.Name = Path.GetFileName(path);
rootRow.TypeId = externalObject.typeId;
// Create an image for this item.
Stream sourceStream = Application.GetResourceStream(new Uri(externalObject.IconUri, UriKind.Relative)).Stream;
MemoryStream iconStream = new MemoryStream();
CategoryPage.Copy(sourceStream, iconStream);
rootRow.Image = Convert.ToBase64String(iconStream.ToArray());
// Add this new record to the data model.
DataModel.DataSet.Root.AddRootRow(rootRow);
// If a viewer was provided, then make a property for it.
if (String.IsNullOrEmpty(externalObject.ViewerUri))
{
DataSet.PropertyStoreRow viewerPropertyRow = DataModel.DataSet.PropertyStore.NewPropertyStoreRow();
viewerPropertyRow.PropertyId = PropertyId.Viewer;
viewerPropertyRow.PropertyStoreId = Guid.NewGuid();
viewerPropertyRow.RootId = rootRow.RootId;
viewerPropertyRow.Value = externalObject.ViewerUri;
DataModel.DataSet.PropertyStore.AddPropertyStoreRow(viewerPropertyRow);
}
// Create the metadata for the creation date.
DataSet.PropertyStoreRow dateCreatedPropertyRow = DataModel.DataSet.PropertyStore.NewPropertyStoreRow();
dateCreatedPropertyRow.PropertyId = PropertyId.DateCreated;
dateCreatedPropertyRow.PropertyStoreId = Guid.NewGuid();
dateCreatedPropertyRow.RootId = rootRow.RootId;
dateCreatedPropertyRow.Value = DateTime.Now;
DataModel.DataSet.PropertyStore.AddPropertyStoreRow(dateCreatedPropertyRow);
// Create the metadata for the creation time.
DataSet.PropertyStoreRow dateModifiedPropertyRow = DataModel.DataSet.PropertyStore.NewPropertyStoreRow();
dateModifiedPropertyRow.PropertyId = PropertyId.DateModified;
dateModifiedPropertyRow.PropertyStoreId = Guid.NewGuid();
dateModifiedPropertyRow.RootId = rootRow.RootId;
dateModifiedPropertyRow.Value = DateTime.Now;
DataModel.DataSet.PropertyStore.AddPropertyStoreRow(dateModifiedPropertyRow);
// This will load a binary version of the file into the metadata.
using (FileStream fileStream = new FileStream(path, FileMode.Open, FileAccess.Read))
{
MemoryStream memoryStream = new MemoryStream();
CategoryPage.Copy(fileStream, memoryStream);
DataSet.PropertyStoreRow dataPropertyRow = DataModel.DataSet.PropertyStore.NewPropertyStoreRow();
dataPropertyRow.PropertyId = PropertyId.Data;
dataPropertyRow.PropertyStoreId = Guid.NewGuid();
dataPropertyRow.RootId = rootRow.RootId;
dataPropertyRow.Value = Convert.ToBase64String(memoryStream.GetBuffer(), 0, Convert.ToInt32(memoryStream.Length));
DataModel.DataSet.PropertyStore.AddPropertyStoreRow(dataPropertyRow);
}
// This will create an association between the parent item and the object just created.
DataSet.TreeRow treeRow = DataModel.DataSet.Tree.NewTreeRow();
treeRow.ParentId = categoryCollection.RootId;
treeRow.ChildId = rootRow.RootId;
treeRow.TreeId = Guid.NewGuid();
DataModel.DataSet.Tree.AddTreeRow(treeRow);
// This will insert the new object in the View Model at the given location in the hierarchy.
categoryCollection.Leaves.Add(new CategoryCollection(categoryCollection, rootRow));
}